From: Arnd Bergmann
These four architectures define the same Kconfig symbols for configuring
the page size. Move the logic into a common place where it can be shared
with all other architectures.
Signed-off-by: Arnd Bergmann
---
Changes from v1:
- improve Kconfig help texts
- fix Hexagon Kconfig
arch/Kconfig | 92 ++-
arch/hexagon/Kconfig | 24 ++--
arch/hexagon/include/asm/page.h | 6 +-
arch/loongarch/Kconfig| 21 ++-
arch/loongarch/include/asm/page.h | 10 +---
arch/mips/Kconfig | 58 ++-
arch/mips/include/asm/page.h | 16 +-
arch/sh/include/asm/page.h| 13 +
arch/sh/mm/Kconfig| 42 --
9 files changed, 121 insertions(+), 161 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index a5af0edd3eb8..c63034e092d0 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1078,17 +1078,105 @@ config HAVE_ARCH_COMPAT_MMAP_BASES
and vice-versa 32-bit applications to call 64-bit mmap().
Required for applications doing different bitness syscalls.
+config HAVE_PAGE_SIZE_4KB
+ bool
+
+config HAVE_PAGE_SIZE_8KB
+ bool
+
+config HAVE_PAGE_SIZE_16KB
+ bool
+
+config HAVE_PAGE_SIZE_32KB
+ bool
+
+config HAVE_PAGE_SIZE_64KB
+ bool
+
+config HAVE_PAGE_SIZE_256KB
+ bool
+
+choice
+ prompt "MMU page size"
+
+config PAGE_SIZE_4KB
+ bool "4KiB pages"
+ depends on HAVE_PAGE_SIZE_4KB
+ help
+ This option select the standard 4KiB Linux page size and the only
+ available option on many architectures. Using 4KiB page size will
+ minimize memory consumption and is therefore recommended for low
+ memory systems.
+ Some software that is written for x86 systems makes incorrect
+ assumptions about the page size and only runs on 4KiB pages.
+
+config PAGE_SIZE_8KB
+ bool "8KiB pages"
+ depends on HAVE_PAGE_SIZE_8KB
+ help
+ This option is the only supported page size on a few older
+ processors, and can be slightly faster than 4KiB pages.
+
+config PAGE_SIZE_16KB
+ bool "16KiB pages"
+ depends on HAVE_PAGE_SIZE_16KB
+ help
+ This option is usually a good compromise between memory
+ consumption and performance for typical desktop and server
+ workloads, often saving a level of page table lookups compared
+ to 4KB pages as well as reducing TLB pressure and overhead of
+ per-page operations in the kernel at the expense of a larger
+ page cache.
+
+config PAGE_SIZE_32KB
+ bool "32KiB pages"
+ depends on HAVE_PAGE_SIZE_32KB
+ Using 32KiB page size will result in slightly higher performance
+ kernel at the price of higher memory consumption compared to
+ 16KiB pages. This option is available only on cnMIPS cores.
+ Note that you will need a suitable Linux distribution to
+ support this.
+
+config PAGE_SIZE_64KB
+ bool "64KiB pages"
+ depends on HAVE_PAGE_SIZE_64KB
+ Using 64KiB page size will result in slightly higher performance
+ kernel at the price of much higher memory consumption compared to
+ 4KiB or 16KiB pages.
+ This is not suitable for general-purpose workloads but the
+ better performance may be worth the cost for certain types of
+ supercomputing or database applications that work mostly with
+ large in-memory data rather than small files.
+
+config PAGE_SIZE_256KB
+ bool "256KiB pages"
+ depends on HAVE_PAGE_SIZE_256KB
+ help
+ 256KiB pages have little practical value due to their extreme
+ memory usage. The kernel will only be able to run applications
+ that have been compiled with '-zmax-page-size' set to 256KiB
+ (the default is 64KiB or 4KiB on most architectures).
+
+endchoice
+
config PAGE_SIZE_LESS_THAN_64KB
def_bool y
- depends on !ARM64_64K_PAGES
depends on !PAGE_SIZE_64KB
- depends on !PARISC_PAGE_SIZE_64KB
depends on PAGE_SIZE_LESS_THAN_256KB
config PAGE_SIZE_LESS_THAN_256KB
def_bool y
depends on !PAGE_SIZE_256KB
+config PAGE_SHIFT
+ int
+ default 12 if PAGE_SIZE_4KB
+ default 13 if PAGE_SIZE_8KB
+ default 14 if PAGE_SIZE_16KB
+ default 15 if PAGE_SIZE_32KB
+ default 16 if PAGE_SIZE_64KB
+ default 18 if PAGE_SIZE_256KB
+
# This allows to use a set of generic functions to determine mmap base
# address by giving priority to top-down scheme only if the process
# is not in legacy mode (compat task, unlimited stack size or
diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index a880ee067d2e..1414052e7d6b 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -8,6 +8,10 @@ config HEXAGON
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select
